Sometimes, as a molecular modeler, you run into compatibility issues with datasets, specific extensions, or institutional setups that make it necessary to use an older version of your favorite simulation platform. If you’re using SAMSON, the integrative molecular design platform, you’ll be happy to know that installing an older version is not only possible—it’s also straightforward. Here’s a complete guide on how to do it, including how to manage multiple versions without conflicts. 🧬
Why revert to an older version?
While the latest version of SAMSON is typically the most stable and feature-rich, there are valid reasons why you might need an earlier release:
- Some SAMSON Extensions are only available or stable on older versions.
- Your collaborators or institutional tools may require a specific SAMSON version.
- You’re reproducing results from a published workflow that was based on a prior release.
Step-by-step: Installing an older version
Installing an older version of SAMSON uses the same installer as the latest one. Just follow this process:
- Download the standard SAMSON installer from SAMSON Connect.
- During the installation, at the second step, check the option “Install an older version”.
- Then, choose the version you want to install. Keep in mind that versions are identified by developer numbers (e.g., 2.0.2 corresponds to the 2021 version).
To find out which developer number matches which year/version, you can consult the User Guides for other SAMSON versions.
Managing multiple installations
If you’re working with different SAMSON versions, you might need to manually launch the correct one. Here’s how you do that on various operating systems:
- Windows:
C:/Users/%USERNAME%/OneAngstrom/SAMSON-Application/<version>/Binaries/SAMSON-Core.exe - MacOS:
$HOME/Applications/SAMSON.app/ - Linux:
$HOME/OneAngstrom/SAMSON-Application/<version>/Binaries/SAMSON-Core.sh
This gives you full control over which version you use on demand—perfect for switching between projects or comparing results across releases.
Good to know:
- Most SAMSON Extensions are updated only for the latest version. Extensions may behave differently or not work at all on older versions.
- When it’s time to upgrade again, the current installer will let you do so while preserving your data and existing setups.
Installing an older version of SAMSON can help ensure consistency, compatibility, and confidence in your molecular modeling workflows.
To learn more, visit the full SAMSON FAQ documentation.
SAMSON and all SAMSON Extensions are free for non-commercial use. You can get started by downloading SAMSON at https://www.samson-connect.net.